Using Multi-phase CT Radiomics Features to Predict EGFR Mutation Status in Lung Adenocarcinoma Patients.

RATIONALE AND OBJECTIVES: This study aimed to non-invasively predict epidermal growth factor receptor (EGFR) mutation status in patients with lung adenocarcinoma using multi-phase computed tomography (CT) radiomics features. MATERIALS AND METHODS: A total of 424 patients with lung adenocarcinoma were recruited from two hospitals who underwent preoperative non-enhanced CT (NE-CT) and enhanced CT (including arterial phase CT [AP-CT], and venous phase CT [VP-CT]). Patients were divided into training (n = 297) and external validation (n = 127) cohorts according to hospital. Radiomics features were extracted from the NE-CT, AP-CT, and VP-CT images, respectively. The Wilcoxon test, correlation analysis, and simulated annealing were used for feature screening. A clinical model and eight radiomics models were established. Furthermore, a clinical-radiomics model was constructed by incorporating multi-phase CT features and clinical risk factors. Receiver operating characteristic curves were used to evaluate the predictive performance of the models. RESULTS: The predictive performance of multi-phase CT radiomics model (AUC of 0.925 [95% CI, 0.879-0.971] in the validation cohort) was higher than that of NE-CT, AP-CT, VP-CT, and clinical models (AUCs of 0.860 [95% CI,0.794-0.927], 0.792 [95% CI, 0.713-0.871], 0.753 [95% CI, 0.669-0.838], and 0.706 [95% CI, 0.620-0.791] in the validation cohort, respectively) (all P < 0.05). The predictive performance of the clinical-radiomics model (AUC of 0.927 [95% CI, 0.882-0.971] in the validation cohort) was comparable to that of multi-phase CT radiomics model (P > 0.05). CONCLUSION: Our multi-phase CT radiomics model showed good performance in identifying the EGFR mutation status in patients with lung adenocarcinoma, which may assist personalized treatment decisions.

Isoliquiritigenin Inhibits the Growth of Colorectal Cancer Cells through the ESR2/PI3K/AKT Signalling Pathway.

Colorectal cancer (CRC) is one of the most common malignancies. Isoliquiritigenin (ISL), a flavonoid phytoestrogen, has shown anti-tumour activities against various cancers. However, its anti-CRC mechanism has not been clarified. In this study, the potential molecular mechanism of ISL against CRC was investigated through network pharmacological prediction and experimental validation. The results of the network prediction indicate that ESR2, PIK3CG and GSK3ß might be the key targets of ISL against CRC, which was verified by molecular docking, and that its anti-tumour mechanisms might be related to the oestrogen and PI3K/AKT signalling pathway. The experimental results show that ISL reduced the viability of SW480 and HCT116 cells, induced apoptosis, blocked the cell cycle in the G2 phase in vitro, and suppressed xenograft tumour growth in vivo. In addition, ISL significantly down-regulated the protein expression of PIK3CG, AKT, p-AKT, p-GSK3ß, CDK1, NF-κB and Bcl-2; up-regulated ESR2 and Bax; decreased the ratio of p-AKT/AKT and p-GSK3ß/GSK3ß; and increased the Bax/Bcl-2 ratio. This study indicates that ISL can inhibit the growth of CRC cells and induce apoptosis, which may be related to the up-regulation of ESR2 and inhibition of the PI3K/Akt signalling pathway.

A study on factors associated with age of Alzheimer's disease onset / 中华流行病学杂志

Objective: To understand the distribution characteristics of age of Alzheimer's disease (AD) onset and influencing factors. Methods: Based on the follow-up data of Alzheimer's Disease Neuroimaging Initiative from 2005 to 2022, participants with normal cognition (CN) or mild cognitive impairment (MCI) at baseline survey, and those with progression to AD during follow-up period were selected as study subjects. Univariate analysis and multiple linear regression analysis were performed to explore the associations of gender, race, number of ApoE ε4 genes carried, family history, years of education and marital status with the age of AD onset. Results: A total of 405 participants, with an average age of (74.0±6.9) years at baseline survey, progressed to AD during follow up period. The age of AD onset was (76.6±7.5) years, and age of onset in men was about 1.9 years later than women. Multiple linear regression analysis showed that for each increase in ApoE ε4 gene number, the age of AD onset was about 0.344 years earlier. The age of AD onset was 4.007 years earlier for those with MCI at baseline survey compared with those with CN. Years of education were not significantly associated with the age of onset of AD (P>0.05). Conclusion: Those who carry ApoE ε4 gene, and have MCI at baseline survey might have earlier age of AD onset.

The value of dual-energy spectral CT in differentiating solitary pulmonary tuberculosis and solitary lung adenocarcinoma.

Background: To explore the value of dual-energy spectral CT in distinguishing solitary pulmonary tuberculosis (SP-TB) from solitary lung adenocarcinoma (S-LUAD). Methods: A total of 246 patients confirmed SP-TB (n = 86) or S-LUAD (n = 160) were retrospectively included. Spectral CT parameters include CT40keV value, CT70keV value, iodine concentration (IC), water concentration (WC), effective atomic number (Zeff), and spectral curve slope (λ70keV). Data were measured during the arterial phase (AP) and venous phase (VP). Chi-square test was used to compare categorical variables, Wilcoxon rank-sum test was used to compare continuous variables, and a two-sample t-test was used to compare spectral CT parameters. ROC curves were used to calculate diagnostic efficiency. Results: There were significant differences in spectral CT quantitative parameters (including CT40keV value [all P< 0.001] , CT70keV value [all P< 0.001], λ70keV [P< 0.001, and P = 0.027], Zeff [P =0.015, and P = 0.001], and IC [P =0.002, and P = 0.028]) between the two groups during the AP and VP. However, WC (P = 0.930, and P = 0.823) was not statistically different between the two groups. The ROC curve analysis showed that the AUC in the AP and VP was 90.9% (95% CI, 0.873-0.945) and 83.4% (95% CI, 0.780-0.887), respectively. The highest diagnostic performance (AUC, 97.6%; 95% CI, 0.961-0.991) was achieved when all spectral CT parameters were combined with clinical variables. Conclusion: Dual-energy spectral CT has a significant value in distinguishing SP-TB from S-LUAD.

Network analysis and experimental pharmacology study explore the protective effects of Isoliquiritigenin on 5-fluorouracil-Induced intestinal mucositis.

5-fluorouracil (5-FU) is one of the most widely used chemotherapy drugs for malignant tumors. However, intestinal mucositis caused by 5-FU is a severe dose-limiting toxic effect and even leads to treatment interruption. Isoliquiritigenin (ISL) is one of the main active compounds of licorice, which is a traditional Chinese herbal medicine commonly used in inflammation and gastrointestinal diseases. It is speculated that ISL have protective effects on intestinal mucositis. However, no such studies have been reported. Therefore, to investigate the impact of ISL on 5-Fu-induced intestinal mucositis, a strategy based on network prediction and pharmacological experimental validation was proposed in this study. Firstly, the targets and mechanism of ISL in alleviating 5-Fu-induced gastrointestinal toxicity were predicted by network analysis. And the results were further confirmed by molecular docking. Then, a mouse model of intestinal mucositis was established by intraperitoneal injection of 5-FU (384 µmol/kg) to verify the prediction of network analysis. The network analysis results suggested that PTGS2 (Prostaglandin G/H synthase 2) and NOS2 (Nitric oxide synthase, inducible) might be the critical targets of ISL for reducing the intestinal toxicity of 5-FU. In addition, KEGG and GO enrichment analysis revealed that the HIF-1, TNF, MAPK, IL-17, PI3K-Akt, Ras, NF-kappa B signaling pathway, and biological processes of the inflammatory response, apoptosis regulation, NO production and NF-kappa B transcription factor activity might be involved in the mechanism of ISL against intestinal mucositis. Subsequent animal experiments showed that ISL could reduce the weight loss, leukopenia and mucosal damage caused by 5-FU. Compared with the intestinal mucositis model, the protein expressions of PTGS2, NOS2, TNFα (Tumor necrosis factor-alpha) and NF-κB p65 (nuclear factor kappa-B P65) were decreased after ISL treatment. In conclusion, this study is the fist time to find that ISL can attenuate 5-FU-induced intestinal mucositis in mice. Its anti-mucositis effect may be through regulating TNF/NF-κB pathway and inhibiting inflammatory mediators PTGS2 and NOS2. It will provide a potential candidate for the prevention and treatment of chemotherapy-induced intestinal mucositis.

Calycosin suppresses colorectal cancer progression by targeting ERß, upregulating PTEN, and inhibiting PI3K/Akt signal pathway.

High intake of phytoestrogen has been reported to be associated with the prevention of colorectal cancer (CRC). Calycosin belongs to the phytoestrogen that has been shown to suppress CRC cells in our previous study. However, its anticancer activity and molecular mechanisms have not been elucidated. In this study, we analyzed the effect of calycosin on the viability and apoptosis of human CRC HCT116 and SW480 cells via MTT assay, flow cytometry assay, and caspase-3/7 activity assay. The protein expressions of estrogen receptor ß (ERß), PTEN, and PI3K/Akt signal pathways were determined by Western blot analysis. And then, the alterations of biological behavior in CRC cells transfected with ERß siRNA were analyzed. Mouse xenograft models were further performed to detect the antitumor effect in vivo. The results show that calycosin reduces CRC cell viability, induces cell apoptosis, and suppresses xenograft tumor growth. The protein expressions of ERß and PTEN are significantly upregulated following calycosin treatment, whereas p-AKT/AKT ratio and Bcl-2 level are downregulated. Suppressing ERß with siRNA partially attenuates the reduction in viability and apoptosis induced by calycosin. Our results indicate that calycosin shows inhibitory effects on CRC cells, which might be obtained by targeting ERß, upregulating PTEN, and inhibiting the PI3K/Akt signal pathway.

Application and Evaluation of the Flipped Classroom Based on Micro-Video Class in Pharmacology Teaching.

With the continuous development of information technology, new teaching resources "micro-video class" and teaching model "flipped classroom" have gradually attracted the attention of teachers. Whether and how they can be applied in pharmacology teaching has already become the focus of medical education research in recent years. This paper explores the application and evaluation of the flipped classroom based on micro-video class in pharmacology teaching in our college. Students in Class 1 and Class 2 majoring in clinical medicine of 2018 in Chengdu Medical College were randomly divided into experimental group and control group. The teaching model of flipped classroom based on micro-video class was used in the experimental group, while the traditional teaching model was used in the control group. Theory tests and questionnaires were carried out at the end of the course. The average scores of theoretical knowledge in experimental group were significantly higher than those in control group (P < 0.05). In addition, the results of the feedback questionnaire showed that the overall satisfaction of students participating in flipped classroom based on micro-video class was higher (P < 0.05), and students thought that their learning enthusiasm, learning efficiency, and abilities of autonomous learning and problem-solving were greatly improved compared with those of students taught applying the traditional teaching model. Flipped classroom based on micro-video class model successfully improved the outcome of pharmacology teaching. It is supposed to provide reference for the reform of pharmacology teaching in medical college.

Transition rules of cognitive frailty and influencing factors in the elderly in China / 中华流行病学杂志

Objective: To understand the transition rules of cognitive frailty and its influencing factors in the elderly in China and provide evidence for the early intervention of cognitive frailty. Methods: Data were retrospectively collected from China Health and Retirement Longitudinal Study with 3 round consecutive survey (2011, 2013, 2015) and the state of the subjects were classified into four categories: robust-normal cognitive, cognitive impairment, physical frailty, and cognitive frailty. A multi-state Markov model was established to explore the transition rules of cognitive frailty and its influencing factors. Results: A total of 3 470 older adults were included, and 350 (10.09%) had cognitive frailty at baseline. After two years, the probability of cognitive frailty in the cognitive impairment population was higher than that in people with physical frailty (31.6% vs. 7.6%). Persons with cognitive frailty were more likely to become physical frailty (29.7% vs. 15.6%). Being women (HR=1.599, 95%CI: 1.058-2.417), comorbidity (HR=3.035, 95%CI: 1.090-8.450), and depression (HR=1.678, 95%CI: 1.153-2.441) were the risk factors associated with cognitive frailty in the elderly, while being educated (HR=2.367, 95%CI: 1.567-3.575) was a protective factor for the transition of cognitive frailty to physical frailty. Conclusions: The prevalence of cognitive frailty is relatively high in the elderly in China. Those with cognitive impairment have a higher probability of cognitive frailty. Gender, education level, comorbidity, and depression are the main influencing factors for the occurrence and transition of cognitive frailty.

Research on predicting the risk of mild cognitive impairment in the elderly based on the joint model / 中华流行病学杂志

Objective: To construct and compare the dynamic prediction models of the risk of mild cognitive impairment (MCI) in the elderly based on six different cognitive function scales. Methods: Based on longitudinal data from the Alzheimer's Disease Neuroimaging Initiative from 2005 to 2020, Mini-mental state examination (MMSE), functional activities questionnaire (FAQ), Alzheimer's disease assessment scale-cognitive (ADAS-Cog) 11, ADAS-Cog13, ADAS delayed word recall (ADASQ4), and Rey auditory verbal learning test (RAVLT)_immediate were used as longitudinal cognitive function evaluation indicators to assess the longitudinal changes in cognitive function. The joint model was used to analyze association between indicators variation trajectory and survival outcome MCI, and construct the risk prediction model of MCI in the elderly, the linear mixed model was constructed the longitudinal sub-model which described the evolution of a repeated measure over time, a proportional hazards model was constructed the survival sub-model, and the two sub-models were connected through the correlation parameter (α). The areas under the receiver operator characteristic curve (AUC) were used to evaluate the predictive efficacy of the model in the follow-up period of (t, t+Δt). The starting point t was selected at the 30th, 42nd, and 54th month, and the Δt was selected as 15 and 21 months. Based on the prediction model, an example of the research object was selected for dynamic individual predictions of the risk of MCI. Results: Finally, 544 older adults (aged 60 years and above) with normal baseline cognitive status were included, of which 119 cases (21.9%) had MCI during the follow-up process were regarded as the case group, and 425 cases remained normal as the control group. The joint model suggests that the longitudinal trajectories of the six evaluation indicators are all related to the risk of MCI (P<0.001). The risk of MCI decreased by 32.3% (HR=0.677, 95%CI: 0.541-0.846) and 10.8% (HR=0.892, 95%CI: 0.865-0.919) for each one-point increase of MMSE and RAVLT_immediate longitudinal scores. The risk of MCI increased by 53.2% (HR=1.532, 95%CI: 1.393-1.686), 36.2% (HR=1.362, 95%CI: 1.268-1.462), 23.2% (HR=1.232, 95%CI: 1.181-1.285), and 85.1% (HR=1.851, 95%CI:1.629-2.104) for each one-point increase of FAQ, ADAS-Cog11, ADAS-Cog13, and ADASQ4 longitudinal scores. AUC results show that RAVLT_immediate (0.760 2) and ADASQ4 (0.755 8) have higher average prediction efficiency, followed by ADAS-Cog13 (0.743 7), ADAS-Cog11 (0.715 3), FAQ (0.700 8) and MMSE (0.629 5). ADASQ4 joint model was used to provide a dynamic individual prediction of the risk of MCI. The average probability of MCI after five years of follow-up and ten years of follow-up in the example individuals were 8% and 40%, respectively. Conclusions: The RAVLT_immediate and ADASQ4 scales, which are only for memory tests, have high accuracy in predicting the risk of MCI. Using the RAVLT_immediate and ADASQ4 scales as longitudinal cognitive function evaluation indicators to construct a joint model, the results can provide a basis for realizing MCI risk prediction for the elderly.

Licorice Ameliorates Cisplatin-Induced Hepatotoxicity Through Antiapoptosis, Antioxidative Stress, Anti-Inflammation, and Acceleration of Metabolism.

Cisplatin (CP) is one of the most effective antitumor drugs in the clinic, but has serious adverse reactions, and its hepatotoxicity has not been fully investigated. Licorice (GC), a traditional herbal medicine, has been commonly used as a detoxifier for poisons and drugs, and may be an effective drug for CP-induced hepatotoxicity. However, its mechanism and the effector molecules remain ambiguous. Therefore, in this study, a network pharmacology and proteomics-based approach was established, and a panoramic view of the detoxification of GC on CP-induced hepatotoxicity was provided. The experimental results indicated that GC can recover functional indices and pathological liver injury, inhibit hepatocyte apoptosis, upregulate B-cell lymphoma/leukemia 2 (Bcl-2) and superoxide dismutase (SOD) levels, and downregulate cellular tumor antigen p53 (p53), caspase-3, malondialdehyde high mobility group protein B1 (HMGB1), tumor necrosis factor alpha (TNF-α), and interleukin 1ß (IL-1ß) levels. Proteomics indicated that GC regulates phosphatidylcholine translocator ABCB1 (ABCB1B), canalicular multispecific organic anion transporter 1 (ABCC2), cytochrome P450 4A2 (CYP4A2), cytochrome P450 1A1 (CYP1A1), cytochrome P450 1A2 (CYP1A2), estrogen receptor (ESR1), and DNA topoisomerase 2-alpha (TOP2A), inhibits oxidative stress, apoptosis, and inflammatory responses, and accelerates drug metabolism. In this study, we provide the investigation of the efficacy of GC against CP-induced hepatotoxicity, and offer a promising alternative for the clinic.

Proteomic Investigations of Transcription Factors Critical in Geniposide-Mediated Suppression of Alcoholic Steatosis and in Overdose-Induced Hepatotoxicity on Liver in Rats.

Alcoholic steatosis is one of the most prevalent forms of liver disease, and appropriate insight and application of anti-steatosis drugs must be considered. Geniposide, the major active constituent of the Gardenia jasminoides (Ellis) fruit, has been commonly used as a traditional herbal medicine for the treatment of liver diseases. However, its hepatoprotective effect on alcoholic steatosis has not been reported. Moreover, geniposide overdose-induced hepatotoxicity was demonstrated. Hence, its therapeutic effects and overdose-induced hepatotoxicity in rat models along with corresponding targets, especially the targets of transcription factors (TFs), were systematically investigated in this study by using a concatenated tandem array of consensus TF response elements. The results indicate that geniposide can attenuate alcoholic steatosis and liver injury by enhancing the transcriptional activities of peroxisome proliferator-activated receptor-α and hepatocyte nuclear factors 1α and 4α, while geniposide overdose perturbs other TFs. In addition, therapeutic doses and overdoses of geniposide have differentiated target TFs. This study is the first to provide a systematic insight into the difference of critical transcription factors between the actions of therapeutic doses and overdoses of geniposide, as well as much-needed attention to the important topic of alcoholic liver disease therapy.

Precise and systematic survey of the efficacy of multicomponent drugs against functional dyspepsia.

Functional dyspepsia (FD) is one of the most prevalent functional gastrointestinal disorders, and more and more multicomponent drugs represented by traditional Chinese medicines have provided a favorable therapeutic effect in its treatment. However, their precise localization in the clinic, as well as corresponding mechanism, is ambiguous, thus hindering their widespread use. To meet this requirement, a precise and systematic approach based on a restriction of special disease-related molecules and the following network pharmacology analysis was developed and applied to a multicomponent conventional drug, XiaoErFuPi (XEFP) granules. Experimental verification of the results indicates that this approach can facilitate the prediction, and the precise and systematic efficacy of XEFP could be easily revealed, which shows that XEFP has an advantage over the positive control drug on lactate, gastrin, interleukin 4 and calcitonin gene-related peptide. Moreover, by the proteomics analysis, its superposition of multi-target effects was revealed and a new candidate target for the treatment of FD, striatin, was obtained and verified. This study provides a practicable precise approach for the investigation of the efficacy of multicomponent drugs against FD and offers a promising alternative for the systematical management of FD.

[Rat plasma metabolomics in blood stasis model based on ultra performance liquid chromatography-quadrupole-time-of-flight mass spectrometry].

Acute blood stasis syndrome was induced in rats by adrenaline hydrochloride and ice water. Ultra performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF/MS) was conducted on plasma metabolites of normal and model rats. Principal component analysis (PCA), differentiation analysis of supervised partial least squares method (PLS-DA), and orthogonal to partial least squares discriminant analysis (OPLS-DA) on metabolomics data for multidimensional statistical analysis were employed, and the resulting biomarkers were screened. Compared to the normal group, there were 46 endogenous metabolites in blood stasis-rat plasma. Of these, 21 metabolites were significantly upregulated, such as acetylcholine, N6,N6,N6-trimethyl-L-lysine, cytosine, and acetylcarnitine, while 25 metabolites were reduced, including indoleacrylic acid, and lysoPC(14:0). These metabolites were mainly related to metabolic pathways, including lipid metabolism, galactose metabolism, linoleic acid metabolism, biosynthesis of unsaturated fatty acids, glycolysis, and arachidonic acid metabolism. In conclusion, these results indicated that metabolites could be used as important biomarkers for blood stasis syndrome, and could help in revealing the mechanism of blood stasis disease and provide a reference network to determine the disease development stage and appropriate follow-up treatment. Studying altered metabolites in blood stasis model rats can provide insights useful for the diagnosis of blood stasis in the clinic and for the development of drug therapies.

[Effects of the fermentation products of endophytes from Glycyrrhiza uralensis on inflammation-associated factors and Aquaporin in rat models with phlegm blocking in lung].

OBJECTIVE: To filtrate the effective fermentation products of endophytes from Glycyrrhiza uralensis by comparing expectorant effects. METHODS: Ninety Wistar rats with half males and half females were randomly divided into 9 groups(n=10):including normal control group, model group, positive control group, Glycyrrhiza decoction group, 5 groups of the fermentation products of endophytes(JTZB005,JTZB006,JTZB043,JTZB060,JTZB063). The model of phlegm blocking in lung was induced by inhaling SO2 for 30 minutes and cold wind for 10 minutes twice per day for ten days. Ten days later, 10 ml/kg normal saline was administrated in normal control group and model group, 0.08 mg/kg Fufang Beimu Lvhuaan tablets was administrated in positive control group, 0.95 g/kg Glycyrrhiza water decoction and the fermentation products of endophytes were respectively administrated in Glycyrrhiza decoction group and 5 groups of the fermentation products of endophytes. All groups were given the corresponding dose by intragastric administration once a day for seven days. The changes of rats' general activities were observed during the experimental time. Two hours after the last gavage, rats were sacrificed. The upper lobe of the right lung was removed for HE and immunohistochemical staining. Pathological of lung tissues and the expressions of aquaporin-1(AQP1)and aquaporin-5(AQP5) in lung tissue were measured. In addition, the lung tissue of middle lobe of right lung were accurately weighed, and 10% homogenate were made. The supernatant was removed by centrifugation at 3 000 r/min for ten minutes. The levels of nitric oxide (NO) was determined by nitric acid reductase method. The content of tumor necrosis factor(TNF-α) and intercellular adhesion molecule 1(ICAM-1) and the concentration of cyclooxygenase-2(COX-2) in lung tissue were measured by enzyme-linked immunosorbent(ELISA) method. RESULTS: After modeling,the levels of NO, TNF-α, ICAM-1, and the concentration of COX-2 in lung tissue were increased significantly, the expressions of AQP1 and AQP5 were decreased significantly (P<0.01). Compared with the model group, the levels of NO,TNF-α,ICAM-1 and the concentration of COX-2 in lung tissue were decreased significantly, and the expressions of AQP1 and AQP5 were increased significantly in Glycyrrhiza decoction group, JTZB005,JTZB006 and JTZB063 group(P<0.05, P<0.01). CONCLUSIONS: By filtrating, JTZB005、JTZB006、JTZB063 have expectorant effects.

Pathway-based analysis tools for complex diseases: a review.

Genetic studies are traditionally based on single-gene analysis. The use of these analyses can pose tremendous challenges for elucidating complicated genetic interplays involved in complex human diseases. Modern pathway-based analysis provides a technique, which allows a comprehensive understanding of the molecular mechanisms underlying complex diseases. Extensive studies utilizing the methods and applications for pathway-based analysis have significantly advanced our capacity to explore large-scale omics data, which has rapidly accumulated in biomedical fields. This article is a comprehensive review of the pathway-based analysis methods-the powerful methods with the potential to uncover the biological depths of the complex diseases. The general concepts and procedures for the pathway-based analysis methods are introduced and then, a comprehensive review of the major approaches for this analysis is presented. In addition, a list of available pathway-based analysis software and databases is provided. Finally, future directions and challenges for the methodological development and applications of pathway-based analysis techniques are discussed. This review will provide a useful guide to dissect complex diseases.

Laryngeal aerodynamic analysis in assisting with the diagnosis of muscle tension dysphonia.

OBJECTIVE/HYPOTHESIS: To estimate the aerodynamic multiparameters for patients with muscular tension dysphonia (MTD) and evaluate voice aerodynamic analysis for assisting the diagnosis of this disorder. STUDY DESIGN: A prospective study. METHODS: Voice aerodynamic parameters, including subglottal pressure (SGP) level, glottal resistance (GR), mean airflow rate (MFR), and maximum phonation time (MPT), for 26 MTD patients and 27 normal adults were analyzed using receiver operating characteristics (ROC) analysis and multivariate logistic regression. RESULTS: For male samples, MTD patients had higher SGP (P=0.001), higher GR (P=0.012), lower MFR (P=0.042), and shorter MPT (P=0.027), whereas for female samples, the difference between cases and controls was statistically significant only in SGP (P<0.001) and MPT (P<0.001). ROC analysis showed that the threshold of 8.175 cm H(2)O for SGP achieved a good classification for MTD, with an adequate sensitivity (76.9%) and the perfect specificity (100%). Finally, multivariate logistic regression established a credible model (with SGP and MPT as the predictors) for classifying MTD, with a 92.5% percentage correct. CONCLUSIONS: This analysis indicates that aerodynamics evaluation could help the diagnosis of MTD patients, jointly with medical history scrutiny, physical examination, fibrolaryngoscopy, and/or videoendostroboscopy.

Fatigue cyclic loading test of an auro-galvanoforming ceramic bridge.

BACKGROUND: In dental clinics, dentition defects are commonly restored with conventional porcelain-fused-to-metal fixed bridges. However, Ni-Cr alloy ceramic fixed bridges are known to have several drawbacks such as marginal coloration of the neck, low casting precision and, most seriously, poor biocompatibility. These problems could be circumvented by using noble metal ceramic bridges; however, one negative issue related to the conventional noble metal ceramic bridges is its high price due to the use of a large amount of gold for pontic. Therefore, an auro-galvanoforming ceramic bridge would be ideal to retain the advantages of a conventional material, yet reduce the amount of noble metal used. This study aimed to investigate whether any destructive changes occur to the auro-galvanoforming ceramic bridge under a fatigue cyclic loading test. METHODS: On standard models which the left maxillary first premolar is lost and with the cuspid teeth and the second premolar as the fixed bridge abutment teeth, six maxillary auro-galvanoforming ceramic bridges and six corresponding nichrome ceramic jointed crowns were made as group A, six nichrome ceramic bridges and six corresponding nichrome ceramic jointed crowns were made as group B (control group). And then all specimens were fixed and tested on a fatigue cyclic loading machine; the changes occurring to the surfaces of occlusal contact with large functional area and to the porcelain-metal interfaces of the nichrome primary copings margins were observed through a scanning electron microscope (SEM). RESULTS: In 120 hours' continual observation, none of the specimens had porcelain coating fractures or scraping occurrence and all of the porcelain coatings had been kept intact under sinusoidal cyclic loading with the load range of 120 - 200 N and frequency of 5 Hz. CONCLUSIONS: Auro-galvanoforming ceramic bridges exhibited excellent fatigue strength in the fatigue cyclic loading test and may satisfy the clinical demand in theory, while the practical application shall be evaluated by observations in long-term clinical usage.

Fatigue cyclic loading test of an auro-galvanoforming ceramic bridge / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>In dental clinics, dentition defects are commonly restored with conventional porcelain-fused-to-metal fixed bridges. However, Ni-Cr alloy ceramic fixed bridges are known to have several drawbacks such as marginal coloration of the neck, low casting precision and, most seriously, poor biocompatibility. These problems could be circumvented by using noble metal ceramic bridges; however, one negative issue related to the conventional noble metal ceramic bridges is its high price due to the use of a large amount of gold for pontic. Therefore, an auro-galvanoforming ceramic bridge would be ideal to retain the advantages of a conventional material, yet reduce the amount of noble metal used. This study aimed to investigate whether any destructive changes occur to the auro-galvanoforming ceramic bridge under a fatigue cyclic loading test.</p><p><b>METHODS</b>On standard models which the left maxillary first premolar is lost and with the cuspid teeth and the second premolar as the fixed bridge abutment teeth, six maxillary auro-galvanoforming ceramic bridges and six corresponding nichrome ceramic jointed crowns were made as group A, six nichrome ceramic bridges and six corresponding nichrome ceramic jointed crowns were made as group B (control group). And then all specimens were fixed and tested on a fatigue cyclic loading machine; the changes occurring to the surfaces of occlusal contact with large functional area and to the porcelain-metal interfaces of the nichrome primary copings margins were observed through a scanning electron microscope (SEM).</p><p><b>RESULTS</b>In 120 hours' continual observation, none of the specimens had porcelain coating fractures or scraping occurrence and all of the porcelain coatings had been kept intact under sinusoidal cyclic loading with the load range of 120 - 200 N and frequency of 5 Hz.</p><p><b>CONCLUSIONS</b>Auro-galvanoforming ceramic bridges exhibited excellent fatigue strength in the fatigue cyclic loading test and may satisfy the clinical demand in theory, while the practical application shall be evaluated by observations in long-term clinical usage.</p>

[Digital speckle correlation method: a technique to evaluate the tensile property of articular cartilage].

OBJECTIVE: To establish a new technique for evaluation of the tensile property of articular cartilage using digital speckle correlation method (DSCM). METHODS: Three specimens of whole layer articular cartilage of the size of 10 mm x 4 mm were prepared from the cartilage of head of femur replaced from a 52-year-old male suffering from fracture of neck of femur (old control), the amputated tibia plateau of a 16-year-old female suffering from osteosarcoma (young control), and the cartilage of head of femur of a 19-year-old female suffering from spondyloepiphyseal dysplasia tarda with progressive arthropathy (SEDT-PA) and then underwent DSCM in U and V fields. RESULTS: The specimens of the 2 controls showed a smooth surface of cartilage and homologous deformation while the specimen of the SEDT-PA patient showed a rough surface of cartilage and deformation with increased undulation. Under a changed loading of 3.3 N the values of average strain of cartilage were 3800, 8800, and 9500 micro epsilon, and the values of tensile elastic modularity were 227.23, 89.59, and 127.25 MPa respectively for the old control, young control, and SEDT-PA patient. The numbers of pixel in U field after 20 pixels were moved in the X direction were significantly different between the old control subject and the SEDT-PA patient (0.101 +/- 0.022 vs 0.220 +/- 0.053, P = 0.023). The numbers of pixel in V field after 20 pixels were moved in the Y direction were significantly different among the old control subject and the SEDT-PA patient. Differences were also significant among the three kinds of cartilage (0.055 +/- 0.018, 0.196 +/- 0.057 vs 0.658 +/- 0.144, both P < 0.05). CONCLUSION: DSCM is a reliable technique to measure the tensile property of articular cartilage, especially for evaluation of small specimens. SEDT-PA is characterized by a dramatic decrease of tensile property, causing destruction and loss of the articular cartilage.